US 11,927,225 B2
Sliding spline shaft device
Shigetoshi Kashiwabara, Kanagawa (JP); Kunio Katada, Kanagawa (JP); Shunsuke Hiraiwa, Kanagawa (JP); Akihumi Kawaguchi, Kanagawa (JP); Takeo Nishijima, Kanagawa (JP); Shinichi Suzuki, Kanagawa (JP); Yasuyuki Katsumada, Kanagawa (JP); Makoto Nakajima, Kanagawa (JP); Tokunori Kodama, Kanagawa (JP); Masato Ito, Kanagawa (JP); and Aiki Iwasa, Kanagawa (JP)
Assigned to NISSAN MOTOR CO., LTD., Yokohama (JP); and NIHON PARKERIZING CO., LTD., Tokyo (JP)
Appl. No. 17/056,471
Filed by NISSAN MOTOR CO., LTD., Yokohama (JP); and NIHON PARKERIZING CO., LTD., Tokyo (JP)
PCT Filed Apr. 12, 2019, PCT No. PCT/JP2019/015959
§ 371(c)(1), (2) Date Nov. 18, 2020,
PCT Pub. No. WO2019/225203, PCT Pub. Date Nov. 28, 2019.
Claims priority of application No. 2018-098939 (JP), filed on May 23, 2018.
Prior Publication US 2021/0199158 A1, Jul. 1, 2021
Int. Cl. F16D 3/06 (2006.01); C09D 7/61 (2018.01); C09D 179/08 (2006.01); C10M 103/06 (2006.01); C10M 107/44 (2006.01); C10M 111/04 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C23C 28/04 (2006.01); C10N 50/00 (2006.01)
CPC F16D 3/06 (2013.01) [C09D 7/61 (2018.01); C09D 179/08 (2013.01); C10M 103/06 (2013.01); C10M 107/44 (2013.01); C10M 111/04 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C23C 28/04 (2013.01); C10M 2201/0663 (2013.01); C10M 2217/0245 (2013.01); C10N 2050/023 (2020.05); F16D 2200/0021 (2013.01); F16D 2200/0034 (2013.01); F16D 2200/0052 (2013.01); F16D 2300/06 (2013.01); F16D 2300/10 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A sliding spline shaft device for an automobile, the sliding spline shaft device comprising:
a male spline; and
a female spline that is fitted to the male spline in an axially slidable manner; wherein:
at least one of the splines has a surface processed layer comprising an undercoat layer, an intermediate layer containing a phosphate, and a topcoat layer containing a solid lubricant and a binder resin, in this order;
the undercoat layer comprises a diffusion layer, and a compound layer containing an iron nitride; and
the compound layer is porous.